docs: def assert_equal(first, second, msg_fmt="{msg}"):
      """Fail unless first equals second, as determined by the '==' operator.
  
      >>> assert_equal(5, 5.0)
      >>> assert_equal("Hello World!", "Goodbye!")
      Traceback (most recent call last):
          ...
      AssertionError: 'Hello World!' != 'Goodbye!'
  
      The following msg_fmt arguments are supported:
      * msg - the default error message
      * first - the first argument
      * second - the second argument
      """
  
      if isinstance(first, dict) and isinstance(second, dict):
          assert_dict_equal(first, second, msg_fmt)
      elif not first == second:
          msg = "{!r} != {!r}".format(first, second)
          fail(msg_fmt.format(msg=msg, first=first, second=second))